The invention relates generally to catheters for use in a body. More particularly, the invention relates to a xe2x80x9cslipxe2x80x9d hub design for use in a percutaneous catheter in a body.
Long term indwelling percutaneous catheters, such as peripherally-inserted central catheters (PICCs), central lines, and hemodialysis catheters, are widely used for a variety of medical applications (e.g., administration of drugs, drawing blood, etc.). These catheters have a rigid hub that is typically sutured to the skin to prevent the catheter shaft from being inadvertently pulled out. More specifically, suture wings are rigidly connected to the hub and sutured to the skin. The catheter shaft extends from the sutured hub, through the skin and underlying tissue, into the vascular system and ends at the junction of the superior vena cava and the right atrial (i.e., the SVC/RA junction). The catheter is maintained in this position over several weeks or months.
During this period of time, the patient is typically fully ambulatory. Since the hub is rigidly fixed to the patient (i.e., via the suture wings) and the catheter shaft is relatively fixed within the percutaneous entry site, all relative motion between these two locations imparts flexural stress on the hub to catheter shaft connection. As the patient moves about over the period of time (e.g., several weeks or months) that the catheter is in use, the rigid connection between the hub and patient focuses all the resulting flexural motion on the hub to catheter shaft connection. Over time, this stress often leads to mechanical failure at the hub to catheter shaft junction, which requires the removal and replacement of the failed catheter. For example, an article entitled xe2x80x9cPICC Lines: Choosing Devices, Placement and Managementxe2x80x9d by Dr. Alan Matsumoto reports a 9.7% mechanical failure rate of the device at the hub to catheter shaft junction.
It is a principle object of the invention to reduce the mechanical failure rate of catheters, such as long term indwelling percutaneous catheters. It is another object of the invention to provide a long term indwelling percutaneous catheter that offers a flexible connection between the hub and suture wings such that a percentage of the flexural motion is absorbed at that area, thereby reducing the stress on the hub to catheter shaft connection and extending the service life of the catheter.
These and other objects are met by a xe2x80x9cslipxe2x80x9d hub design according to the invention. With catheters employing this type of new hub design, the rate of mechanical failure of the catheters (such as long term indwelling percutaneous catheters) is reduced, and the catheters can be maintained in position in patients"" bodies for an extended period of time, such as several weeks, several months, or longer.
The invention features a catheter (such as a long term indwelling percutaneous catheter) that includes an elongated catheter shaft, a hub, and a suture wing component. The elongated shaft has a proximal end and a distal end, where the distal end is for insertion into a body. The distal end of the catheter shaft enters the body at an entry site. The entry site can be a puncture of the skin of the body that leads to a vein within the body into which the catheter shaft is inserted, for example. The hub is located at or near the entry site of the body. A suture wing component is placed over (and surrounds) a portion of the hub. The suture wing component is secured to the skin of the body, or to an anchoring device that is itself secured to the skin of the body, adjacent the entry site. The catheter shaft extends through the hub, through the skin and underlying tissue, and into the vascular system (e.g., into a vein) of the patient""s body such that the distal tip of the catheter shaft can be located at a desired point in the body, such as at the SVC/RA junction. The catheter can be maintained in this position within the body for an extended period of time, such as for several weeks, several months, or longer. The hub includes a section of reduced diameter, which is engaged and surrounded by a portion of the suture wing component. The reduced diameter section allows the hub to move substantially unrestricted translationally (i.e., axially, back and forth along a longitudinal axis of the hub and catheter) and rotationally relative to the suture wing component. In one embodiment, the suture wing component includes a rounded edge adjacent the hub. The rounded edge of the suture wing component allows an additional degree of freedom of relative movement between the hub and the suture wing component, such that the hub can xe2x80x9crockxe2x80x9d within the suture wing component.
The foregoing and other objects, aspects, features, and advantages of the invention will become more apparent from the following description and from the claims.